Computer networking has largely been using dynamic routing protocols for finding the optimal path between two endpoints, with consideration taken only for the availability of endpoints and various forms of cost influencing which path may be selected as the preferred one out of a given set. The default operational mode of routing protocols has no consideration for the capability of the path to deliver the traffic from a quality perspective. The quality issue has been dealt with using other mechanisms including: (a) the use of probing techniques designed to determine packet loss, latency and jitter of the available paths and then using the collected data as input to a secondary path selection process; and (b) employing forward error correction to enable the receiving end to reconstitute messages subject to partial loss along the path enabling the delivery of a complete message to the destination.
Forward error correction is typically only applied to ensure that a given path is capable of delivering traffic despite challenging conditions, primarily related to loss of traffic. An acceptable implementation of forward error correction is typically capable of recovering and constituting the original packets sent despite a loss rate along the path as high as 10%.
The downside of using forward error correction is that using forward error correction requires additional traffic to be sent since the information necessary to reconstitute the original packets is sent in addition to the original traffic, thus consuming additional bandwidth. For this reason, forward error correction has significant drawbacks.
Furthermore, a common reactive measure to adapt to changing conditions in terms of available links, bandwidth or variation in Service Level Agreements (SLAs) is to limit the overall bandwidth available to all applications, to provide for an all-encompassing but equally impactful impairment across all applications and services transiting a device.